Index: Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingFailureMechanismTest.cs
===================================================================
diff -u -r41fac7fff0a505c08945108d795dcb877f10b816 -r89e5c41b732ccf30350026e8d35a01d9a180fdfc
--- Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingFailureMechanismTest.cs	(.../PipingFailureMechanismTest.cs)	(revision 41fac7fff0a505c08945108d795dcb877f10b816)
+++ Ringtoets/Piping/test/Ringtoets.Piping.Data.Test/PipingFailureMechanismTest.cs	(.../PipingFailureMechanismTest.cs)	(revision 89e5c41b732ccf30350026e8d35a01d9a180fdfc)
@@ -218,5 +218,20 @@
             // Assert
             CollectionAssert.DoesNotContain(failureMechanism.CalculationsGroup.Children, folder);
         }
+
+        [Test]
+        public void Contribution_Always_UpdatesNormProbabilityInputContribution()
+        {
+            // Setup
+            var failureMechanism = new PipingFailureMechanism();
+            const double newContribution = 12;
+
+            // Call
+            failureMechanism.Contribution = newContribution;
+
+            // Assert
+            Assert.AreEqual(newContribution, failureMechanism.NormProbabilityInput.Contribution);
+            Assert.AreEqual(newContribution, failureMechanism.Contribution);
+        }
     }
 }
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